I still use a BB Bold 9900. It's a solid machine, figuratively and literally. The new Q10 is not built as solidly (lacks the solid steel border that has saved my phone from several drops in the last 20 months) and it lacks the optical track pad for precision pointing/cursor movement. BB10 OS also lacks bridge functionality with the Playbook tablet. Getting a BB10, for my purposes, would be a downgrade.
Something that most people do not realize about BB 4/5/6/7 OS versions is that the work flow for accomplishing routine tasks is amazing, fast, and can be accomplished with just one's thumb on all the QWERTY phones. Taking a picture and sending it via any of the communication options is a great example of this.
1. Press camera button.
2. Aim and press camera button again to take picture.
3. Press menu button.
4. Trackpad through menu to Send > Email/BBM/SMS/etc.
5. Trackpad choose/type recipient.
Done
When I tried a Windows Phone accomplishing the same thing was so convoluted and frustrating, there was no way in hell I was going to use it instead of a Blackberry. Another great thing about my BB9900 is how simple it is toggle connectivity modes. One tap/click on the main screen and I can change the Cell, Wifi, Mobile Hotspot, Bluetooth, and NFC with a single tap/click. Multiply that sentiment by all of the work flow areas where RIM nailed convenient usability and it's very easy to see value in the platform.
People who stick with their Blackberries do so because they are efficient, extremely stable/reliable, and have many capabilities. My Blackberry always "just works", no muss, no fuss, no frustrations.
That said, I'm not really keen on the work flow and all touch UI paradigm of the BB10 OS. Forsaking the innovation of the optical trackpad was a huge step backward and the insistence on integrating social media with email, sms, and bbm is asinine for those of us who do not use social media and enjoy keeping our communication platforms separate.
All that said, RIM ("Blackberry"...) would be a good match for Microsoft or Sony, because it would give their product lines an instant in road to enterprise mobile computing, the market of folks who simply like the BB best, and the ownership of the QNIX operating system, which in itself is a healthy business.